Liquid rhizobium inoculants have become widely available in recent years. The inoculants are predominantly packaged for sale and shipping in “bag-in-box” (“BIB”) containers, which generally consist of a plastic bag or bladder positioned within a cardboard box. For illustrative purposes, it is understood that BIB containers are used for storing products such as wine and fruit juices.
During transport and storage of liquid inoculants, it is beneficial that the number of viable cells remain high and also that the rhizobium survive when applied to the seed prior to planting. Liquid rhizobial inoculants are not dormant products—the microbial cells are actively respiring, leading to a demand for oxygen. As a result, inoculants packaging must have oxygen permeability. Other microorganisms also require packaging that has oxygen permeability for purposes of storage and transport.
Known BIB containers for packaging liquid rhizobium inoculants use bags made of low density polyethylene (“LDPE”) or related variants such as very low density polyethylene (“VLDPE”). These films are considered to be non-barrier films. That is, they are permeable to oxygen and carbon dioxide. The bladders used in these BIB containers are generally made of single layer films or two-ply films made up of two films that are both made of the same material, which is typically impermeable to liquid.
There is a need in the art for improved packaging for liquid rhizobium inoculants and other microorganisms.